The evaluation of brain natriuretic peptide changes and difficult airway predictors during perioperative period of pregnancy.

Abstract

Airway changes, difficult ventilation, and intubation are the leading causes of morbidity and mortality in pregnancy, but no prospective study has evaluated the relationship between airway changes and brain natriuretic peptide (BNP) before and after cesarean section operations. The purpose of this study was to evaluate the relationship between BNP and airway changes in women undergoing delivery and during the postoperative period. Included in this prospective study were a total of 35 pregnant females with ASA I physical status who were scheduled for cesarean section under general anesthesia. BNP levels, Mallampati classification, mouth opening, thyromental distance, sternomental distance, and the degree of neck extension were recorded before cesarean section and 24 h after the operation. Laryngeal views were also documented after intubation. Significant differences in BNP levels, Mallampati classification, mouth opening, thyromental distance, sternomental distance, and the degree of neck extension measurements arose between initial measurements and those measurements made 24 h postoperatively. Pre-delivery Mallampati I, II, III, IV scores of 6, 18, 7, 4 had by 24 h after cesarean section changed to 13, 13, 6, 3, respectively (p < 0.05). Initial BNP levels were 7.59 ± 6.30; postoperative levels were 52.39 ± 48.17. In this study we found a correlation between perioperative BNP levels and difficult intubation parameters. Within 24 h postpartum, Mallampati scores changed in 13 patients (30.95 %). Besides the correlation between BNP levels and difficult intubation parameters, we also found significant differences in initial and postoperative BNP values.